1. Field of the Invention
The invention relates in general to an electronic apparatus, and more particularly to a head mounted display apparatus and a backlight adjustment method thereof.
2. Description of the Related Art
Along with the advance in technology, people assimilate more and more information every day. The commonly seen multimedia play apparatus, network communication apparatus and computer apparatus are equipped with a CRT or LCD display for displaying images. However, the pixels and size of a displayed image depend on the size and efficiency of the display. Conventional CRT or LCD display cannot meet the requirements of large size and convenient portability at the same time. To resolve the above problem, an optical see-through head mounted display (HMD) apparatus is provided. The optical see-through HMD apparatus allows the user to see the real image of the physical world and the virtual image provided by the head mounted display apparatus at the same time. The head mounted display apparatus has a CRT or LCD display disposed in front of each eye. The head mounted display apparatus projects the image outputted by respective CRT or LCD display onto the user's retina through a beam splitter and creates a 3D effect by using the parallax between the user's two eyes. However, when the luminance level of a virtual image is higher than the ambient light luminance, the user will feel the virtual image projected on the display module dazzling. Conversely, if the ambient light luminance is higher than the luminance of a virtual image, the user will be unable to clearly see the virtual image projected on the display module. Therefore, how to avoid the ambient light luminance affecting the user's visual perception has become a prominent task for the industries.